HYDROGEN H2
General Characteristics
Hydrogen is a flammable, colorless, odorless, nontoxic gas that is lighter than air. It is shipped in steel cylinders under high pressure.
Physical Information
Molecular Weight
2.016
Flammability Limits in air
4.0 - 75.0%
Specific Gravity,
Gas @ 70&degF(21.1&degC),
1 atm(Air=1)
0.07
Density,
Gas @ 70&degF
(21.1&degC), 1 atm
0.0052lbs/ft^3 (0.0834g/l)
Specific Volume,
Gas @ 70&degF
(21.1&degC), 1 atm
192.0ft^3/lb (11.99l/g)
Melting Point @ 75.1 psia
(518 kPa)
-434.6&degF (-259.2&degC)
Boiling Point @ 1 atm
-422.98&degF (-252.77&degC)
Critical Temperature
-400.4&degF (-240.2&degC)
Critical Pressure
188.2 psia (12.98 bar)
Toxicity
Non-Toxic, asphyxiant only